Refrigerating apparatus



' INVENTOR ATTORN EYS R. L. LEE

REFRIGERRTING APPARATUS Original Filed Nov. 24, 1950 Dec. 11, 1934.

14% LL U LL.U 'LLL Patented Dec. II, 1934 UNITED STATES PATENT OFF-ICE BEFRIGERATING APPARATUS Ralph L. Lee, Dayton, Ohio, assignor to Frigid aire Corporation, Dayton, Ohio, a corporation of Delaware Application November 24, 1930, Serial No. 497,715 Renewed November. 1, 1933 20 Claim.

Consequently one of the objects of the invention is to provide a refrigerating system including a compressor and improved control means for the compressor so that it may be driven by a continuously operating constant speed driving means.

A more specific object of the invention is to provide an improved unloading devicefor a continuously operated compressor which iscontrolled according to the temperature within the storage compartment of a refrigerator cabinet.

A further object is to provide an improved refrigerating system of the domestic type which will maintain a compartment to be cooled at a substantially constant temperature.

Further objects and advantages of the present invention will be apparent from the following description, reference being bad to the accompanying drawing, wherein a preferred form of the present invention is clearly shown.

In the drawing:

The figure is a diagrammatic illustration of a refrigerating system including a refrigerator cabinet together with a compressor shown partly in section and partly in elevation.

Referring to the drawing, there is shown diagrammatically for illustrative purposes, a refrigerating system of the compressor-condenserexpander type including a compressor 21 for compressing the refrigerant, preferably sulphurdioxide, and for forwarding it through theconduit 90 to the condenser 22 where it .is liquefied and collected in the receiver 23. A supply C0119- duit 26 supplies liquid refrigerant to the evaporator or cooling unit 27 where the liquid refrigerant vaporizes because of the absorption of heat from the food storage compartment 30 of the refrigerator cabinet 31 and this vaporized refrigerant is returned to the compressor through the return conduit 28. The evaporator may be of any suitable type and may be for instance of the float controlled valve type disclosed in the patent to Osborn 1,556,708, patented October 13, 1925.

The compressor 21 is driven by a directly connected electric motor 29.

The compressor 21 is shown as consisting of a casting 35. having a crank case portion 36 and a cylinder portion 37 whlch'may be provided with integral cooling fins 38 to cool the walls of the cylinder portion 37.

Within the crank. case portion 36, opposite aligned bearings 39 and 40.are formed within which a drive shaft 41, driven by th'e'motor 29, is rotatably mounted. Access through the crankcase portion 36 may be had through a removable plate 42 which is fastened to the bottom' of the crank case portion 36 by means of the cap screws 43.

The cylinder portion 37 is provided. with a cylinder bore 44 within which apiston 45 is caused to reciprocate through the medium of an eccentric which is mounted on theshaft 41 and the connecting rod 46 which is connected to A valve (not shown) is provided the eccentric.

in the head of thepiston 45 for admitting-gaseous refrigerant to the compression chamber from the crankcase.

The upper end of the-casting 35 is cut away interiorly to form a seat for a valve an unloading device.

To this end the casting 35 is provided with a passage communicating at its lower end with a crankcase and at its upper end communicating with the upper end of the cylinder bore 44 through a passage 61.

A valve 63 located in the passage 61 is adapted to control communication of the passage 61 with the passage 60 for a purpose hereinafter more fully set forth. This valve 63 is provided with an operating rod 64 secured at its outer end to the movable plate 66 of the sealing bellows 68, the bellows 68 having its other end secured to the outer wall of the casting 35, thus preventing leakage of refrigerant outwardly from the passage'fil along the rod 64 through the packing plug to the atmosphere.

Means are provided. for opening and closing thevalve 63 in accordance with low and high temperatures within the food storage compart ment.30 of a refrigerator cabinet 31.

To this end I provide a bracket 81 having one end connected to the cylinder wall of the casting 35 and its other end connected to the stationary wall 82 of a bellows 72 which has its other movable end 83 secured to a coil spring 75 which is interposed by the removable plate 83 of the bellows 72 and removable plate 66 of the bellows 68 to operate the bellows 64 and the valve 63. A small conduit 85 connects the bellows'72 to the thermostatic bulb 86 positioned within a portion of the food storage compartment 30 of the refrigerator cabinet 31 to expand and contract the bellows 72 for operating the valve 63.

The operation of the device is as follows: The motor 29 operates continuously to drive the compressor at a substantially constant speed when the food storage compartment is relatively warm. The vaporized refrigerant is drawn into the crankcase of the compressor through the return conduit 28 and is drawn upwardly through the valve in the head of the piston into the compression chamber at the top of the cylinder bore 44 where it is compressed and forced past the valve 53 into the conduit 90 leading to the condenser 22. The compressor thus operates loaded because the relatively warm air in the food storage compartment 30 of the refrigerator cabinet 31 causes the volatile fluid within the thermostatic bulb 86 to expand, forcing volatile fluid through the conduit 85, causing the bellows 72 to expand, thereby moving the movable plates 83 to the right and causing the spring '75 to move the movable plate 66 of the bellows 68 to the right, thus closing the valve 63. Further expansion of the volatile liquid will act only against the tension of the spring '75, thereby preventing rupture of the bellows 68 and injury of the point of the valve 63.

When, the food storage compartment 3'7 is cooled sufficiently, the volatile fluid within the thermostatic bulb 86 will condense and contract, thereby allowing the bellows 72 to contract and to open the valve 63. By opening the valve 63, the refrigerant drawn into the cylinder bore 44 above the head of the piston 45 will be forced to the passage 61 past the valve 63 and through the passage into the crankcase of the compressor, the compressor thereby running unloaded.

In normal operation the valve 63 will not vary merely from one extreme to another but may assume various intermediate positions so as to supply just the correct amount of refrigerant necessary to properly cool the interior of the refrigerator cabinet. If desired, however, means may be provided to make the valve 63 snap acting so that the valve 63 will not assume an intermediate position but will be either open or closed according to the temperature within the refrigerator cabinet.

Thus it will be seen that applicant has provided a compressor having a controlling means so that the compressor may be driven by a continuously operating constant speedmotor so that an intermittent starting and stopping which is common in refrigerating systems now in use, as well as the resultant variation in temperature within the food storage compartment of the cabinet,

avoided.

While the form of embodiment of the invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. Refrigerating apparatus including a cabinet having a storage compartment therein, a cooling unit for said storage compartment, a condenser, a compressor for supplying refrigerant through the condenser to the cooling unit and for withdrawing refrigerant from the cooling unit, means for continuously driving the compressor and means responsive to the temperature within a portion of the storage compartment for unloading the compressor.

2. Refrigerating apparatus including a cabinet having a storage compartment therein, a cooling unit for said storage compartment, a condenser, a compressor for supplying refrigerant through the condenser to the cooling unit and for withdrawing refrigerant from the cooling unit, means for continuously driving the compressor, and thermostatic unloading means for the compressor controlled by a thermostatic bulb responsive to the temperature of the storage compartment.

3. Refrigerating apparatus including a cabinet having a storage compartment therein, a cooling unit for said storage compartment, a condenser, a compressor for supplying refrigerant through the condenser to the cooling unit and for withdrawing refrigerant from the cooling unit, means for continuously driving the compressor, an unloading device for the compressor incorporating a valve for controlling the unloading of the compressor, and thermostatic means for operating the valve including a thermostatic bulb responsive to the temperature of the storage compartment, 2. bellows connected to said valve and means connecting the thermostatic bulb and the bellows.

4. In a compression refrigeration machine, the combination of a constantly driven compressor and a condenser connected with the discharge side of the compressor constituting the high pressure portion of the machine, an evaporator connected with the suction side of the compressor constituting the low pressure portion of the machine, an expansion valve between the condenser and the evaporator, conduit by-pass means connecting said high pressure and low pressure portions, and a thermostatic valve in said conduit by-pass means controlled by temperature changes produced by said evaporator, said thermostatic valve operating to load and unload the compressor.

5. A refrigerating apparatus comprising an object to be cooled, a constantly running motor, a

COIIIDIESSOI, 8, condenser and an evaporator, and

means controlled by temperature conditions in said apparatus for unloading and reloading the compressor whereby to maintain a uniform temperature.

6. A refrigerating apparatus comprising an object to be cooled, a compressor, a continuously running motor for continuously actuating the compressor, a condenser and an evaporator, and thermostatically controlled means for interrupting compression of gas by the compressor when a portion of said apparatus has a predetermined temperature.

7. A refrigerating apparatus comprising an object to be cooled, a compressor, a continuously running motor for actuating the compressor, a condenser and an evaporator, and thermostatically controlled means for unloading and reloading the compressor according to the temperature of a portion of said apparatus.

8. A refrigerating apparatus comprising an object to be cooled, a compressor, a continuously running motor for actuating the compressor, a condenser and an evaporator, and thermostatically controlled means for by-passing the gas discharged from the compressor into the intake a plurality of piston strokes and a check valve v of the compressor at a pressure differential smaller than the diflerential between the condenser and evaporator when a portion of the apparatus reaches a predetermined temperature.

9. In refrigerating apparatus, the combination 'of a compressor, a continuously running motor for actuating the same, a condenser and an evaporator, a by-pass valve for unloading and reloading said motor, a thermostat for operating said valve, said thermostat operating to gradually operate the valve to provide for gradual reloading of the motor.

10. A refrigerating apparatus comprising an object to be cooled, a compressor, a continuously running motor for actuating the compressor, a condenser and an evaporator, and thermostatically controlled means for unloading and gradually reloading the compressor according to the temperature of a portion of said apparatus.

11. In combination, an evaporator, a contin= uousiy running motor, a condenser, a compressor having an intake portion and a discharge portion, means forming a passage connecting said inlet and outlet portions, and a thermostatically controlled valve for opening and closing the passage, said passage being positioned to maintain throughout its length a pressure differential smaller than the pressure differential between said evaporator and condenser.

12. A refrigerating apparatus comprising an object to be cooled, and a refrigerating system including a continuously running compressor having a piston and adapted for intermittent cycles of compressing and non-compressing operation, an evaporator and a condenser, a portion of said system being a high pressure side and a portion of said system being a low pressure side, means for subjecting the piston of said compressor to only one of said pressure sides during a portion of the operating cycle including a plurality of piston strokes and means for preventing high pressure from said high pressure side from entering the evaporator during said portion of the cycle.

13. A refrigerating apparatus comprising an object to be cooled; and a refrigerating system including a continuously running compressor having a piston, an evaporator and a condenser, said piston having a gas intake position and a gas discharge position, and means responsive to the cooling action of said system for supplying gas to said piston at its intake position substantially at the same pressure as the gas discharged at its discharge position.

14. A refrigerating apparatus comprising an object to be cooled, and a refrigerating system including a continuously running compressor having a piston and adapted for intermittent cycles of compressing and non-compressing operation, an evaporator and a condenser, a portion of said system being a high pressure side and a portion of said system being a low pressure side, means for subjecting the piston of said compressor to only one of said pressure sides during a portion of the operating cycle including for preventing high pressure from said high pressure side from entering the evaporator during said portion of the cycle.

15. A refrigerating apparatus comprising an .object to be cooled, and a refrigerating system including a continuously running compressor having a piston and adapted for intermittent cycles of compressing and non-compressing operation, an evaporator and a condenser, a portion of said system being a high pressure side and a portion of said system being a low pressure side, means for subjecting the piston of said compressor to only one of said pressure sides during a portion of the operating cycle including a plurality of piston strokes and a check valve on the high pressure side of said system for preventing high pressure from said high pressure side from entering the evaporator during said portion of the cycle.

16. A refrigerating apparatus comprising an object to be cooled, a compressor, a continuously running motor for continuously actuating the compressor, a high pressure side including a condenser, a low pressure side including an evaporator, a valve in communication with said low pressure side to vary the compressing action of the compressor, and thermostatic means responsive to temperature conditions in said apparatus for actuating said valve.

17. A refrigerating apparatus comprising an object to be cooled, a compressor, a continuously running motor for continuously actuating the compressor, a high pressure side including a condenser, a low pressure side including an evaporator, a valve in communication with said low pressure side to vary the compressing action of the compressor, and thermostatic means responsive to temperature conditions in said object to be cooled for actuating said valve.

18. A refrigerating apparatus comprising in combination an evaporator, a continuously running motor, a condenser, a compressor continuously operated by said motor, and thermostatic means for unloading and reloading the compressor to vary the heat absorbing capacity of said apparatus.

19. A refrigerating apparatus comprising a high pressure side including a compressor, a motor for actuating said compressor at substantially constant speed, a low pressure side including an evaporator, means for varying the compressing action of the compressor while the compressor runs at substantially constant speed to thereby vary the heat absorbing capacity of the low pressure side, and thermostatic means controlling said first mentioned means.

20. A refrigerating apparatus comprising in combination an evaporator, a condenser, a motor, a compressor operated by said motor, and thermostatic means for unloading and reloading the compressor to vary the heat absorbing capacity of said apparatus while the compressor runs at substantially constant speed.

RALPH L. LEE. 

